Method op and apparatus por recording and reproducing sound



B. KWART| N METHOD OF AND APPARATUS FOR RECORDING AND REPRODUCING SOUNDS June 2, 1931;

oz i mal Filed Dec. 2, 1927 FIG.4' Y

FIG.3

- FIG. 6

INVEITOR BERNARD Kwm'rm ATTORNEY R eieeued June 2, 1931 U I STA TES PATE NT OFFICE 3mm xwan'rm, or nnooxmm, NEW YORK Primal Io. 1,781,550, dated November 11, 1930, Serial 80,287,812, filed December 2, 1927. Application for reissiie filed January 8, 1931. Serial No. 507,510.

This invention relates generally to the art of recording and reproducing light pictures and sound waves simultaneously, and more particularly to an apparatus which is capable of synchronously re roducing light and sound impressions which have been recorded upon the production of talking pictures this being the commonl accepted term used where pictures and soun records are'recordedsimultaneously upon a photographic film or the like, many serious difliculties have been encountered in the various attempts to faithfully record and reproduce the sound impressions. These ditliculties have been-espec1ally great and apparently unsurmountable in the reproduction of ensemble music wherein two ormore instruments or voices of distinctl different pitch characteristics must behea'r In the arrangements now generally employed for producing talking pictures, no attempts have been made to record upon'the photographic film the individual sound impressions as produced by the several instruments or voices which make u the ensemble selection and it is primarily or this reason that the results as now attained are so unsatisfactory.

It'is amongthe'objects'of this invention to qua.lity, but the fullness and richness of .sound volume is also seriously, interfered obviate the serious diliiculties which now'tend to preclude the reproduction of more perfect ensemble music by the provision of an ar- .rangement for synchronously reproducing sound impressions of different pitch characteristics which'have been previously recordedupon photographic films or the like, the several instruments or voices of different pitch.

characteristics being individually but synchronously recorded upon a common film for submquent repzoduction in like manner, the arrangement ing such-that it may be utilizedmdst effectively in the'reproduction-of orchestral, band or other ensemble instrumental or vocal music in a better, clearer and more perfect manner than is now possible.

A further object of the invention is the provision of an arrangement whereby a plurality of sound repnoducing units may beused either independently. of-each other or conjointlyin connection with a single photographic film upon which several instruments thickness, the latter bein more suita le for' a sound of lower pitch. single diaphragm designed to reproduce all sounds, whether they be of high or low itch, is never satisfacto inasmuch as the est that can be done in suc a case is to proportion the diaphragm to sounds of average pitch. Not only does this use of a-single dia hra m for reproducing a number of soun s o varying pitches result in sounds, none of which are true in with, especially where it is desired to reproduce I a reater number of instruments or voices o varying pitches. The present in vention obviates all of these objectionable features by providing an arrangement which is operable to insure the maintenance at all times of the individuality of each instrument the provision of an apparatus for recording a plurality of sounds of different Fitch characteristics upon a photographic lm, either independently or in con unction with light pictures, the apparatus or this purpose including a plurality ofsound responsive devices each of which is designatedto individually convert the sound variations emenating from a, particular source of sound into electrical variations, these latter variations being then converted into light variations which are subsequently recorded upon a photographic film. Inasmuch as this invention is primarily concerned with the simultaneous reproductionof lightpictures and sound waves the particular sound responsive de-v I .vices which are herein used for converting sound variations into electrical variations are whatare known in the art as microphones. As is well known these microphones depend for their operation upon the efi'ect'of the sound waves upon a diaphragm, it being further well lmown' as explained in the preceding paragraph that certain diaphragms,

dependmg upon their size and Wei ht, are

moresensitive to certain sounds t an are others. The use, therefore, of a number of microphones or similar sound responsive devices, each of which is designed to respond most fliciently to a particular sound of given pitch characteristics, is of great importance in that it enables a better and more perfect record in this case upon a photographic film) to behad of ensemble music wherein a number of different instruments or voices are employed;

- A still further object of the invention is I the provision of a method for producing a a v dered ina tter, clearer and more perfect' plurality of individual sound records upon a single hotogralphic film at. a film spec correspon 'ng to t at used in the production of motion pictures, the method bemgespecially applicable for use in recording ensemble music wherein it is desired to record the individual sounds respectively obtained from the several instrumentsfor voices. Closely alliedwith this object is the further .provision of a method for separately reproduc ing the sounds as individually recorded u n the photographie film in such manner t at the result ngeensemble selection will be ren-.

manner than is'now possible. 1 v A 'll further object of the invention is the provisionof a multiple sound record comrising a photographic film upon which has individual y recorded the sound impressions-as produced by difierent instruments or voices. a A still further object of'the invention is the provision of a method for produc' a multi 1e sound recordjof an ensemble tion simultaneously with the production of a composite sound record of. the same selection,-

such that the latter may be reproduced independently of the former in the usual manner.

' nerally employed. 1

er objects, andobjects relating to details of construction, arrangementand poration-will appear more fully hereinafter;

The invention consists substantiallyin the combination, construction, loc'ationand relative arrangement of parts, as wells in the method employed in connection therewith, all as will be more -particularly describedhere inafte'r, as shown in the accompanying dra-w mgs and as finally pointed out-in 'the appended claims. l s In the accompanying drawings: a Figure .1 is a di ammatic view' showmg an arrangement or simultaneously makspaced a such t a edge of the-motion icture-film.

ing motion picture and sound records in accordance with the priciples ofthis invention;

1 Figure 2 is arvertical section through the recording apparatus, this section being taken on the line22 of Figure 1;

Figure 3 is a fragmentary view of a combined motion picture and sound record embogying the principles of this invention;

igure 4 is a view similar to Fi re '3 but showing the motion picture recor 'asbeing separate from the sound record, these records having been simultaneously recorded and adapted for duction;

Figure 5 is a diagrammatic view showing an arrangement for simultaneously reproduc ing the motion pictures and sounds as record-' ed upon a photogra hic film in accordance with the principles oi this-invention Figure 6 isa detail view of a-preferr'ed form of microphot adapted for use in the arran meat shown in Figure 5; v

Figure 7 is a" 'ew 'similarto subsequent simultaneous repro-,

Figure 1 but showing an additional set of microphones,

' all of which are of the same type and'c'onnected through a common amplifier to a common recording lamp for producing a sound record which is auxiliary tdthat produced b the arrangement shown in .Figure 1; and

igure8 is a fra sound record which may be produced by the arrangement of a aratus shown in- Figure7.

thereo which illustrates more or less di making the picture and sound records it will be seen that the arrangement employs i a camera10 or similar'apparatus for p otographicall recording motion pictures and sounds. 19 employs the usualmotion picture lm"11, which latter is unreeled from the reel 13,

uently wound upon the reel '14. Secured to t e inside surface of the rear wallof the camera and; extending transversely there across is a quarta'or similar opaque plate provided in theoppositeends thereof with one or more small slits or openings 16. In the particular arrangement shown in. Figures 1 and2 these openings 16 are'four 1n number, two1being to one side of the plate while the remaining two are to the'op 'te side-"thereof, these pairs of openings ing at each pair is opposite Mounted upon the rear wall 0 the camera entary view of a form of Referring now o the drawin and moreparticularly to Figure rocessof taking the pictures and. e SOlllld Vfll'llllilOIlS, to be suhse ammatically the arrangement of apparatus for simultaneously is camera or recording ap aratus- 10 in any suitablemanner are a plurality of recording lamps 17 for throwing lightrays of varyingintensities upon the p otographic film, these recording larxsps beipgl'gnergized by electrical variations p' ucedugh the use of microphones in the manner well-known in I the art. These recording lamps 17 are equal in number to the number of openings 15 provided in the opaque cover 16 each lamp being positioned directly behin its res ective opening such thatthe fluctuating lig t rays emanating from any one of these lamps Wlll produce a record upon the film of the sounds influencing the particular lamp. By prop erly proportioning the openings 16 the width and length of the beams of light that are directed on the film by the several recording lamps ma be rigidly held tothe proper limits. It wi 1 further be seen that the provision of a number of recording lamps arranged to be individually energized ma es it possible to produce upon a common film a corresponding number of sound records, each of which records is produced by the action of different sound waves upon a number of microphones. The recording of the picture upon the film is carried out in the usual manner by the camera 10, the subject of the picture being positioned in front of the camera lens 18'as is most clearly shown in Figure 1. It. may be ,that this subject is a roup of artists playing a number of diiferent instruments, a number of which produce sounds of distinctly difi'erent pitch characteristics. Were all of these sounds tobe collected for subsequent.

translation into electrical variations through the use of a singlemicrophone, the record as produced upon'the photographic film would not be true and faithful to the sounds as originall produced by the various instruments, this or the reason that the single microphone is not well adapted to take with equal efiiciency a number of different sounds of difierent tonal-values.

It is for this reason that the camera 10 isprovided with a number of recording lamps for producing upon a single photographic film a correspon ng number of sound records, each of these records beingof a. sound or sounds of substantially similar pitch value. In order to properly segre to the sounds of different pitch as roduce by the several instruments when p aying in ensemble, a numferent diameters and thic ber of microphones 19 are em loyed, corresponding in number to the num er of recording lamps 17 provided in the camera 10. The diaphra s of the micro hones 19 are of difdia hragm being adapted to take the sounds of ighest pitch while the largest diaphragm,

' is ada ted to takethe'sounds of lowest pitch.

, the several microp ones 19 are respectively connected'to the recording-lamps 17 in the camera, the several microphones being posi;

, tioned with respect tothe source of soundin such manner that eachof said microphones .films are always in proper registry.

esses, the smallest energizing currents for the recording amps Figure 3 shows one form of record as produce by the arrangement hereinbefore .de-

scribed, this record comprising a single strip of photographic film upon which have been simultaneously recorded the motion pictures 21 and the sound records 22, it being observed that four of these latter records have been shown. It is, of course, to beunderstood that a greater or lesser number of sound records may be made upon the photographic film depending altogether upon the number of microphones and sound recording lamps used.

In the production of the combined picture and sound record as shown in Figure 3, the sound recordin lamps 17 are'arranged in the manner shown in Figure 1. v p

It is quite possible, however, to simultaneously record pictures and sounds upon individual photographic films, these separate records being lllustrated in Figure 4. Of course in this latter instance the sound recording lamps 17 are grouped together such that their fluctuatin ra s of light strike the sound record film 23 w ic is arranged to one side of the motion picture film 24, this latter being produced in the usual manner. Both the sound record film 23 and the motion picture film 24 are operated at the same speeds dur- ,which latter are amp ified through intakes best the sounds of that particular pitch ing both the recording process and the repro- Y proper piecing together of the motion picture and sound record films, they are each provided with suitable marks or numbers 25 on the adjacent marginal edges of the two films, the idea being that the films are to be so arranged that corresponding numbers on the Figure 5 illustrates more or less dia matical ly an arran ment for repr ucin the. sounds recordecf upon the sound recor at the same time that the motion picture is thrown u on a suitable screen 26. In order. to efiect t is simultaneous reproduction of the pictures and sounds a comb ned picture pro-' ection .and sound reproducing apparatus is employed, this apparatus bemg indicated generally by the reference numeral 27.

box 28 provided with t e usual lenses 29 and 30 and the light source 31. The photographic film 11 travels through the apparatus in the usual manner. In the particular arrange- It. will be seen that this ap aratus 27 comprises a;

to that shown in Fi re 3, the motion pictures being recorded in the central portion of the film while the! sound records are recorded 5 upon the film to either side of the motion -picture record. The rays of light fromthe source 31 are so confined that they pass through the central or motion picture record portion of the film. Extending transversely ance of this cell is still further decreased.

Included in the'circuitwith'these neon tubes is a solenoid 40 which'isoperable; when energized, to'cause a shutter 41 at the rear of the- 38. The light from this external source 43 from side to side of the box 28 is an opaque also serves to decrease the resistance of' the partition 32, the central portion thereof bein provided with an opening 33 throu h whic the light rays from the source of lig t 31 are projected upon the motion picture portion of the film. This partition 32 is further provided with small slits or openin 34 arranged to either side of the central opening 33. These smallslits or openings 34 are each in registry with the sound record portions of the film 11.

. A suitable light source 35 is provided for each of the slits or openings 34 and is arranged with respect to its respective opening in such manner that the rays of lig 1t emanating therefrom are directed upon the=particular sound record passing in front of said opening.

. The sounds as recorded. upon the film 11 are reproduced by means of a photo-electric cell or similar device which is influenced by the fluctuating light variations caused by the several sound records passing their respective light sources 35. separate photo-electric cell is employed for each record. As is well-known in the art these electric'cells have the property of converting alight variations into electrical variations. It sometimes happens, however, that the light variations are not strong enough to influence the photo-electric cells, and for this 40 reason it is preferable to substitute for these photo-electric cells devices hereinafter called micro-phots. i 1

These micro-phots are designated generally in Figure 5 by the reference numeral 36,

one of which is shown in detail in Figure 6.

It will be seenthat this micro-phot mmprises a substantially semi-spherical casing 37 within which is arranged, in any suitablemanner, a photo-electric cell or cells 38, this latter cell being adapted to be influenced by of the micro-phot, the resulting light rays acting to influence the photo-electric cell 38 will be of. varying intensity-depending'uporr the character of the sound impressions re-' corded upon the photogra hic film. Within the interior of the micro-p ot casing 37 are a plurality of neon-tubes 39 which are so influ- Y enced' b the electrical variations produced by the p oto-electric celLthat they are caused to light up and so throw additional light rays upon thecell, the .result being that theresistindividualsound photo photo-electric cell with the result that the resistance of this cell is reduced to an irreduclble minimum, the consequence being that a maximum final flow of current will .be obtained which is an exact magnified tween the light source 35 and the micro-phot.

It will be understood that a separate microphot isemployed for each individual sound record; the arrangement of these micro-pilots within the projection apparatus being diagrammatically shown in Figure 5. It will further be observed that each of the microphots 36r is connected to an individual loud speaker or similar telephone receiver 44 through a separate amplifying circuit 45. These loud speakers, 44, are provided with diaphragms of different sizes and weights exactly as in the case of the microphones used in the arrangement for recording the sounds upon the photographic film, the diaphragms of the several loud speakers being so designed that each is best adapted to reproduce sounds of particularpitches. In other'words, thediaphragm of any one of the loud speakers 44 which is influenced by one of the sound rec- 'gords on the film 11 18 so designed as to be most efliciently responsiveto the same frequency of vibration as was the diaphragm will be understood that while the arrangement shown inFigure 1 "permits the of the] microphone ilsed inrecording the particular sound record in question.

duced independently of the former by the simple expedient of cuttingoff the light source 31. In similar manner'the motion pictures maybe reproduced inde endently of the sound records by cutting o the sources oflight 35. Again, it'is quite possible by this arrangement to reproduce any one or 'more of the particular'sound records simply by using only the particular light source of sources 35 correspondingto the sound records which itis desired to reproduce. This'last mentioned feature is" an importantlone in that it permits the reproduction of the sounds produced bycertain of th'e'instruments or voices playlng in ensemblfas for instance,

whem'it might be desirable toreproducethe music from a group of violins ,formi'ng only part of a large group of/difl'erent instruments, the loud s eaker used for this purpose being that w 'ch is most responsive to the pitch or tonal qualities of the violins.

Figure 7 shows a modified arrangement wherein, in addition to the microphones 19, each-of which is responsive to tones of differentpitch,'a second set of microphones 46 is employed, each of these latter microphones being of the same design and not individually responsive to tones of different pitch. The sounds as produced, for instance, y an orchestra; are commonly collected by this additional set of microphones 46 in the' usual manner now generally employed, the electrical variations set up'by these microhones being amplified in a common amplifymg unitk47. This amplified current is then i sent to an auxiliary recording lamp 48 for producing a sound record 49 upon the film of all of the sounds (produced b the orchestra. This sound recor 49 is auxi iary to the in-.

dividual records made upon the film in the manner hereinbefore described.

It will be seen that the arrangement shown in Figure 7 makes it possible to produce s'imultaneously upon the same or separate films two records of the same music, one of these records being divided into a plurality of records of sounds produced by instruments of different pitch, while-the other record is of the usual type wherein is included all of the sounds pro uced by all of the instruments. The record as produced b the arrangement shown in Figure 7 may ta e the form shown in Figure 8, the com site record bein indic ated as at 49 and t e divided recor being indicated as at 50. The importance of pro-' A ducing two such records is that in those cases where it may be too expensive a proposition to employ a number of microhots and loud speakers for producing the in iv-idual sounds or where perfection of reproduction is not essential, the composite record .49 may b'e used in conjunction with a single micro-phot and a single reproducing instrument.

Another important featureof the arrangiment shown in Fi re 7 is that it permits-t recording of music in the usual manner simultanenously with the recordin of music in the im roved manner herein fore .de-

scribed. t. is, of course, to be understood that the composite record 49 may be recorded upon 5 film which is separate from and independent of the film upon which the indi- '.vidual sounds of difierent v itches 'are recorded, and further that hot the composite 'record 49 and the divided sound record 50 V rendered independently of the sound record.

' It is to be understood that various changes may be made from'time to time in the method,

from the spirit or rinicples of the invention, and it is accor 'ngl intended to claim the same broadly, as we indicated by the a pended claims.

1W 113A; is claime 2s new]: and uselful is:

apparatus or p otogra icall roducin upon a photographicfiln i a luza ity of in vidual records of sounds of i'stinctly difierentpitch characteristics, said apparatus as specifically, as

- 5 hereinbefore described without departing.

comprlslng a casing, means for moving the v difi'erent sounds upon the film, and a plurality of sound responsivedevices having diaphragms of varying mass and size each selectively responsive to sounds of difl'erent pitch forproducing said difl'erent electrical variations'.

2. An arrangement for simultaneously recording and simultaneoustlly reproducing sound waves of distinctly di erent frequencies originatin in unison including a pluralit of son responsive devices havin diap ragms o difieflrent mass and size eac selectively responsiv to sound waves of different frequencies f r converting said sound waves intdeletrical variations of corresponding frequencies, a plurality of light producing energization by the electrical variations set up by the several sound responsive devices, said hLfht producing devices being each adapts to produce a record upon'a photodevices arranged for respective.

graphic film of the sound vibrations correspending to the electricallvalxtioni 11:0 vfihich ur 'ty 0 ig t reit has been subjected, a s onsive devices each-a apted to convert the uctuating rays of light produced as each 'of the several records passes a source of light into corresponding electrical "variations, and a. plurality of sound reproducing devices having diaphragms of different mass and size res ctivel corresponding to those of said.

p6 y each electrically responsive devicesan'd be connected toone of said lig t nsive devices for conve .theelectrica .variations set up by the latter into corre onding sound vibrations, said sound rep ucing devices being selectively responsive to electrical variations corresponding in frequencies the v original sound ,waves.

'8. In an apparatus for photpgra'hically producing e'record of sounds, in comb ination,

a plurality of sound responsive devices hav- 05 apparatus and arrangement of apparatus ing diaphragms of varyingmassandsizeeach -ducing devices respectivel and a plurality spectively inc selectively responsive to sound waves of different frequencies for converting said sound waves into electrical variations ofi correspondmg frequencies, an auxiliary sound responsive device havinga' diaphragm com.-'

monly responsive to all of said sound waves,

of'light roducing devices reuded int e electrical circuits of the several sound responsive devices including said auxiliary device, the li ht proinclude in the circuits of said plurality 0 sound responsive devices having diaphragms of varying mass and size being ada ted to produce separate tographic film of the records upon a p sound vibrations of difi'erentfrequencies and the light producing device included in the circuit of said-auxiliary sound responsive device being adapted to produce a composite record upona photographic film of allof the sound l vibrations.

4. In-an apparatus for photographically recording sound vibrations of different frequencies, in combination, means for photographically producing separate records of the sound vibrations of different frequencies and auxiliary means for simultaneously roducing photographically ageparate an dividually repro ucible composite record of 7 all of the sound vibrations irrespective of any difference in the frequencies thereof.

5. .In an apparatus for photographically recording sound waves of distinctly difierent frequencies originating in unison, in combi-'- nation, a-plura ity of means each selectively responsive to the sound'wav esof different frequencies for photognbphically producin individual records Q waves, and additional meanscommonly re,-

sponsive to all of the sound waves for simultaneously roducin photographically a separate and 'ihdividu l reproducible compos ite record of all of sai sounds.

6. In'an apparatus for recording sound waves of distinctly difierent frequencies originating in unison, in combinaton, a plurahty. of sound responsive devices having diaphrams of different mass and size each selectlvely responsive to sound waves of different frequencies, for converting said sound waves into electrical variations of correspondinglfrequencies, an auxiliary sound" reauxiliary sponsive device having a diaphram themass and size of which is an ap roximate aver of those of said first mentioned devices, said vice being responsive to all of e different soun sounds produced by a number of instruments or voices of different pitch characteristics playing in vunison, in combination, means for indilpendently and selectively recordin upon a p otographic film the sounds of di erent pitches produced by the several instruments or voices, and means for hotographicall recording a single'and individually repro uciblecomposite record of the sounds c'ommonly produced by all of the instruments or voices, said last-mentioned means being operable simultaneously with said first-mentioned means.

-8. A method of recording sounds of difl'erent frequency characteristics which consists in establishing electrical current variations corresponding to sound vibrations of approximately like frequency, in maintaining,

the current variations corres ending to the sound vibrations of a given requency sepa-' rate and distinct from those corresponding to sound vibrations of a difierent frequency, in separately establishing electrical current variations corresponding to the composite sound vibrations of dissimilar frequencies,

and in respectively subjecting light roducingelements to the influence of sai plurality of separate photo a hicrecords of the sound vibrations o difierent frequency and a separate and independently re- 'producible composite record of all of said sound vibrations.

In-testimony whereo fixed my signature.

BERNARD KWARTIN.

, I ghave hereunto afsaid soundwaves, and a plurality of light 7 producing elements res ectively included in v the electrical circuits 0 all of the sound re-' sponsive devices, said elements being respec tively adapted to"prodi1ce individually and selectively reproducible photographic records of the sound waves respectively received by the several sound'responsive devices.

I 7. In an apparatus for recordingthe I diifer-' 'ent current variations whereby to produce a 

